Fuel carburetor with central air intake



Sept. 12, 1961 H. w. M CLAIN FUEL CARBURETOR WITH CENTRAL AIR INTAKE Filed Sept. 29, 1958 Era-1 in i ZIIIIIIIIIIII-IIIIIIII 2,999,674 FUEL CARBURETOR WITH CENTRAL Am INTAKE Harry W. McClain, 5460 El Parque, Long Beach 4, Calif. Filed Sept. 29, 1953, Ser. No. 764,074 3 Claims. (Cl. 261- 59) This invention relates to a fuel carburetor with central air intake which feeds gaseous or liquid fuel to an engine.

An object of my invention is to provide a novel fuel carburetor in which the fuel is introduced at substantially the vertical center line of the carburetor, and the air is introduced also at or adjacent to the vertical center line of the carburetor so as to admix with the incoming fuel.

Another object of my invention is to provide a novel fuel carburetor in which the fuel metering valve is mounted on the annular air valve and moves therewith to synchronize the quantity of fuel introduced to the carburetor with the volume of air entering the same.

Another object of my invention is to provide a novel fuel carburetor of the character stated, in which the incoming path of the fuel and the incoming air are substantially parallel to each other and flow downwardly into the carburetor along the vertical center line of the carburetor, thus providing less restriction to the flow of both fuel and air.

Still another object of my invention is to provide a novel fuel carburetor which is simple in construction, inexpensive to manufacture, and which can be easily and quickly adjusted to the proper fuel-air ratio which might be desired.

Other objects, advantages and features of invention may appear from the accompanying drawing, the subjoined detailed description and the appended claims.

In the drawing FIGURE 1 is a vertical sectional view of my carburetor.

FIGURE 2 is a perspective view of the upper half of the carburetor housing.

FIGURE 3 is a perspective view of the annular air valve.

FIGURE 4 is a fragmentary vertical sectional view of a slightly modified form of air valve.

Referring more particularly to the drawing, the numeral 1 indicates the carburetor housing consisting of a mixture outlet portion 2 and a mixture and fuel inlet portion 3. The portion 2 is provided with a flange 4 which bolts onto the intake manifold of the engine in the usual and well known manner. A throttle valve 5, also usual and well known in the art, is provided in the throat 6 of the portion 2 to control the flow of fuel and air into the engine. A flange 7 is formed on the upper edge of the housing portion 2 for the purpose of connecting the parts 23 of the housing, as will be further described.

The upper part 3 of the housing consists of a vertical annular wall 8 which is open at both the top and the bottom. An annular flange 9 on the bottom of the wall 8 enables the top portion 3 to be bolted to the flange 7 by means of the bolts or cap screws 10. The upper portion of the housing 3 also includes a vertical centrally positioned tube 11 which is fixedly or integrally connected to the wall 8 by means of the web 12 on one side, and a fuel intake pipe 13 on the other. The fuel intake pipe 13 may be integrally formed with the tube 11 and also cast with the wall 8, or it may be welded to these parts or otherwise fixedly attached to them for the purpose of providing an adequate support for the tube 11, and to accurately position that tube concentric with the vertical center line of the housing 1. A fuel pipe 14 is attached to the pipe 13 and either gaseous or liquid fuels are pumped or forced into the pipe 13 and thence into the Patented Sept. 12, 1961 carburetor housing 1, as will be further described. The air intake portion 3 of the carburetor is thus provided with two arcuate air intake passages 15 and 16, these passages being arranged on each side of the fuel pipe 13 and the web 12.

An air valve 17 consists of an annular ring, as shown in FIG. 3, and the ring is also provided with a diametn'c web 18 which is arranged below the plane of the ring 17. A boss 19 on the bottom of the tubular portion 11 is substantially the same diameter as the inner diameter of the ring valve 17. Thus when the ring valve 17 is in its raised position it engages or seats on the boss 19, thus shutting olf the flow of air to the carburetor. A coil spring 20 bears against the air valve 17 to urge the valve upwards to its closed position. A guide pin 21 depends from the web 12 and extends through the ring portion of the valve 17 to guide the air valve in its vertical movement. A conical fuel valve 22 is fixedly mounted on the web 18 and moves vertically with the air valve 17.

A guide plug and fuel jet 23 is threaded into the tube 11 and can be adjusted vertically in this tube for the purpose of adjusting the fuel flow, as will be described. A sleeve 24 depends from the plug 23- and a seat 25 is provided at the lower end of the sleeve and cooperates with the needle valve 22 to govern the flow of fuel into the carburetor. A plurality of fuel holes 26 are provided in the sleeve 24 to admit fuel into the sleeve and thence to the seat 25 where the fuel passes the needle valve 22 on its movement into the carburetor. The plug 23 is formed with a counterbore 27 which receives a guide rod 28 formed on the upper end of the needle valve 22. Thus the needle valve 22 is accurately guided in its vertical movement with the annular air valve 17. Suitable packings 29 and 30 are pressed into their seated position by the coil spring 31, thus preventing the leakage of the fuel around the sleeve portion 24 of the plug 23.

In FIG. 4 I have shown a modified type of air valve consisting of aflexible annular diaphragm 32 which is fixedly attached at its outer edge between flanged portions 33 of the wall 34 of the carburetor. The wall 34 is similar to the wall 8 previously described. The central tubular portion 11 is the same as previously described, as is also the plug 23-. A web 35 is secured to the inner edge of the diaphragm 32 and the needle valve 22 is attached to this web and moves therewith in a manner previously described. A coil spring 36 engages the diaphragm 32 to press the diaphragm upwardly and urge a ring 3 7 on the top of the diaphragm into closed position, cooperating with the boss 19 of the air intake portion of the carburetor. Thus again the air is admitted at substantially the vertical center line of the carburetor and joins with the flow of fuel which is also at the vertical center line of the carburetor.

In operation A proper orifice is provided between the needle valve 22 and the seat 25 by adjusting the plug 23, that is, by screwing this plug into or out of the tube 11. Fuel flows through the pipe 13 and thence through the holes 26 and then downwardly substantially parallel to the vertical center line of the carburetor around the needle valve 22. The partial vacuum in the engine which is exerted in the throat 6 will cause the annular air valve 17 to move downwardly away from the boss 19 and against the tension of the spring 20. Air then flows through the arcuate passages 15-16 also in a vertical direction and also inwardly and substantially parallel to the vertical center line of the carburetor. The incoming air thus flows coaxially with the incoming fuel and these component parts are mixed and carried past the throttle valve 5 and thence into the engine.

Having described my invention, I claim:

1. A fuel carburetor comprising a housing, said housing having a mixture outlet thereon and a connection means to attach the same to an intake manifold, a central tube onthe housing arranged substantially in alignment with the vertical center line of the housing, a fuel intake pipe extending into said tube above the lower end thereof, said housing having air passages in the top thereof surrounding said tube, a ring-shape air valve Within the housing cooperatively associated with said tube and said air passages to close the air passages in one position of the air valve, spring means bearing against the air valve to urge the same to closed position, a plug threaded into said'tube and longitudinally adjustable within the tube, a sleeve depending from the plug, said sleeve having fuel ports extending through the wall thereof to admit fuel from said fuel intake pipe, seat means in the sleeve, a needle valve, means mounting the needle valve on the air valve, said needle valve cooperating with said seat to control fuel flow into said housing, said plug having a counterbore extending vertically therein, and a guide rod extending from the needle valve into the counterbore to guide the needle valve in its movement.

2. A fuel carburetor comprising a housing, said hous ing consisting of a lower portion having a mixture outlet thereon and a connection means to attach the same to an intake manifold, an upper portion of the housing, means detachably securing the upper portion of the housing to the lower portion of the housing, a central tube on the upper portion of the housing arranged substantially in alignment with the vertical center line thereof, a fuel intake pipe extending into said tube, the upper portion of said housing having air passages in the top thereof surrounding said tube, an annular air valve in the upper portion of the housing cooperatively associated with the lower end of said tube and said air passages to 4 close the air passages in one position of the air valve, spring means bearing against the aid valve to urge the same to closed position, a seat means in said tube, a needle valve mounted on said air valve and cooperating with said seat to control fuel flow into the housing.

3. A fuel carburetor comprising a housing, said housing consisting of a lower portion having a mixture outlet thereon and a connection means to attach the same to an intake manifold, an upper portion of the housing, means detachably securing the upper portion of the housing to the lower portion of the housing, a central tube on the upper portion of the housing arranged substantially in alignment with the vertical center line thereof, a fuel intake pipe extending into said tube, the upper portion of said housing having air passages in the top thereof surrounding said tube, an annular air valve in the upper portion of the housing cooperatively associated with the lower end of said tube and said air passages to close the air passages in one position of the air valve, spring means bearing against the air valve to urge the same to closed position, a plug threaded into said central tube, a seat means on said plug adjacent the lower end thereof, a fuel intake pipe admitting fuel above said seat, a needle valve mounted on said air valve and cooperating with said seat to control fuel flow into the housing.

References Cited in the file of this patent UNITED STATES PATENTS 974,033 Daniel Oct. 25, 1910 1,961,413 Dansreaw June 5, 1934 1,977,661 Whitehurst Oct. 23, 1934 2,128,079 Dawes Aug. 23, 1938 2,841,374 Raynor July 1, 1958 2,939,776 McClain June 7, 1960 

